Here is an easy way to handle this requirement, making use of Adagio's ability to copy documents within a batch.
0. Create 4 new terms codes in AR, say "SPLITX", "SNET30", "SNET60", and "SNET90" due, 0, 30, 60 and 90 days.
-(this is only done once)-
then...
1. Invoice the big order in Order Entry, assigning the term "SPLITX" to the order.
2. Run dayend as usual.
3. In Receivables, edit the batch. (You might want to put the Terms code on the grid).
4. Make 3 copies of the original invoice.
5. Edit each invoice, changing the invoice number from "xxxx" to "xxxx-0", "xxxx-1", "xxxx-2" etc. and the terms to adjust the appropriate Due dates and amount. (Copy and paste can be used to easily copy the invoice number with the dash, and the calculator can be "popped up" in the invoice amount field to calculate the proportionate amount.)
6. Check that the batch total is still equal to the invoice credit note audit list. (You might want to use GridView or Crystal Reports for this.)
7. Post the batch.
I should note that this looks way more tedious than it is. I did it and it took me about 3 minutes for an invoice (and this was the first time). You could easily create a couple of Crystal reports that could be used as control reports to make sure that the amounts are all adjusted properly.
Also, this procedure adjusts the Due dates of the invoices, not the document date itself. Revenue will be recognized in the period of the sale. A slightly different procedure would have to be followed if you wanted different revenue recognition.